Martin Luther King Jr. had a dream, and it was not for blacks to spend decades lagging behind whites when it comes to economic opportunity. But since King led the “March on Washington for Jobs and Freedom” on August 28, 1963, significant economic gaps between blacks and whites have persisted.

Take unemployment for example. Over the last 50 years, the jobless rate for blacks has consistently been twice as high as the rate for whites, according to the Economic Policy Institute. In 1963 the ratio of black unemployment to white unemployment was 2.2; in 2012 it was 2.1.

Another key indicator is household income. During the period in question, the real median household income for blacks has ranged from the mid $20,000s to the low $30,000s. Compare that to the range for whites: from the upper $40,000s to the mid $50,000s. In 1967, the median black household earned 55% of what the median white household earned. By 2011, that gap had nudged up only to 59%.

Also, the Urban Institute reported: “From 1983 to 2010, average family wealth for whites has been about six times that of blacks and Hispanics—the gap in actual dollars growing as average wealth increased for both groups.”

The persistent inequality has really impacted black children, who are far more likely than white children to live in areas of concentrated poverty: 45% vs. 12%.